Hyperloop’s system works more like a train, with fewer stops and with larger capsules able to handle cargo.

The core idea behind tube transport, what ET3 calls “space travel on Earth,” comes down to eliminating friction from air and rolling resistance so that high speeds can be achieved using minimal energy.

Oster estimates that an early system could move passengers at 370 mph for in-state trips and 700 mph over longer distances. He envisions a day when tubes will carry passengers internationally at 4,000 mph, reducing the trip time between New York and Beijing to less than two hours at a fare one-tenth that of a plane flight.

Tube travel isn’t a new concept. Rocket scientist Robert Goddard proposed the idea in the early 1900s, but several technological advancements make it more workable.

Modern linear electric motors can now rapidly propel vehicles — what riders experience when modern roller coasters shoot them uphill — and regenerative braking technology can capture that energy on the other side.

Magnetic levitation has become more affordable, and a version developed in China that ET3 favors called High Temperature Superconducting Maglev works well in a tube environment.

HTSM eliminates the need to electrify a guideway, but it has a nasty penchant for forming ice and attracting metal, something an airtight tube would eliminate.

Modern vacuum pumps and seals make it much easier to maintain airless environments, and computer technology allows for the precise timing of vehicles moving at high speeds, Oster said.

Ted Smathers, a retired engineering professor at the Colorado School of Mines, said the physics of tube transportation aren’t in question and that the materials and components now exist to build a system.

What ET3 faces now is an engineering challenge, bringing everything together in a way that is affordable and that the traveling public will accept.

“The real issue is making an effective test function that will validate what the theory says can be done,” Smathers said.

Oster said he is working toward that end. He is negotiating for a 3-mile stretch of land, with an estimated cost of $30 million between right-of-way and construction.

Talks are most advanced in Las Vegas, including a route that could connect the airport to The Strip, he said. Oster said he is willing to consider any location with high tourist traffic that would allow ET3 to recoup its costs and win public acceptance, and he said others have come forward since Musk’s announcement.

To fund development, Oster is using an open-source licensing model borrowed from the software world. ET3 counts 290 licensees in 20 countries who have paid $100 per person and $1,000 or more per company.

By keeping initial costs low, Oster said, the idea is to tap the expertise and resources of more licensees, who pledge to pay a royalty of 6 percent of the added revenue the technology generates for them.

“We made it cheaper to cooperate,” he said.

He eventually sees borrowing a business model used for early railroads where investors purchase rights to a stretch of the tube or a capsule, earning rent from them.

Jeff Phillips, owner of Colorado Foundation Systems in Loveland, signed on as a licensee about six weeks ago and is working with Oster on ways to quickly and efficiently plant foundations for towers.

“I have never been a big fan of flying,” Phillips said of why the technology interests him.

Oster and Phillips argue that screwpiles can be drilled at one-third of the cost of placing caissons, which require moving dirt and pouring concrete.

Mark Bunger, research director at Lux Research in San Francisco, said any estimates about tube travel — including costs, speeds and energy consumption — are just that until a system is built.

He also adds that political protest, especially against expensive and inefficient public-transit systems, is driving Musk and other technologists toward tube travel.

Musk suggests that a Hyperloop could move passengers between Los Angeles and San Francisco in 35 minutes for a $20 fare on infrastructure costing one-tenth of what California bureaucrats are proposing for a high-speed bullet train that Musk calls already outdated.

ET3 met with resistance when it applied under the Colorado Department of Transportation’s Advanced Guideway System feasibility study to reduce congestion between Denver and the ski resorts along Interstate 70, Oster said.

David Krutsinger, CDOT’s transit and rail-program manager, said that of 18 submissions, ET3 was among seven that didn’t provide enough information for the department to complete an evaluation.

An analyst’s report shows it was rejected on two measures: safety and the readiness of the technology.

Oster counters that criteria were repeatedly changed when it became apparent ET3 could beat every other alternative by a wide margin on multiple measures.

Building a successful prototype will prove the critics wrong, he said.

Aldo Svaldi has worked at The Denver Post since 2000. His coverage areas have included residential real estate, economic development and the Colorado economy. He's also worked for Financial Times Energy, the Denver Business Journal and Arab News.

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